The captain of the 1979 Victorian Under 17's team, McCarthy graduated from that year's Metropolitan Scholarship Squad to be a Under 19's premiership player in 1981.

Despite this success the rover failed to make the Demons reserves team for 1982 and was sent to play for Parkdale. He was soon recalled to the seconds and kicked four goals on a game which earned him a senior debut. He played six games in 1982, and another six the next year despite a bust-up with Chairman of Selectors Barry Richardson before leaving the club.

McCarthy crossing to the SANFL in 1984 where he played five games for Norwood that year, then at West Torrens.